The project will develop a Hand-Held cancer biomarker monitor based on imunochromatographic technology and nanoparticle based electrochemical immunoassay for rapid, sensitive, and low- cost detection of cancer biomarkers in human blood samples. Breast cancer biomarkers including carcinoenbryonic antigen (CEA), CA15-3 and human mammaglobin will be used as model biomarkers to demonstrate the proof of principle. The principle of the proposed device is based on nanoparticle-powered multiplex bioelectrochemical immunodetection and immunochromatographic separation technique. The multiplex capabilities and significant signal amplification of electrochemical immunoassay are realized conveniently by the use of multiple metallic phosphate nanoparticle labels. Integrating with immunochromatographic separation technology, the new biosensor microanalysis device will provide a portable, sensitive, simple, and low-cost tool for the rapid detection of multiple breast cancer biomarkers. The complete assay time will be less than 10 minutes and the detection limits are 10 times lower than the cutoff values. The device will be used to detect the samples from breast cancer patients and the results will be validated with traditional enzyme-linked immunosorbent assay (ELISA). If the project is successful, the proposed device will be an effective and innovative tool in aiding early cancer diagnosis, monitoring response to therapy and providing real-time prognostic information in patients with cancers. The developed device can also be applied for the detection of other cancer biomarkers. PUBLIC HEALTH RELEVANCE: Cancer is a major and increasing public health problem worldwide. In US, it is the second leading cause of death, just behind heart disease. It is estimated around about 565,650 Americans are expected to die of cancer, more than 1,500 people a day (Cancer Facts and Figures, 2008). The key to decrease the death rate is to detect the cancers as early as possible. However, the majority of patients are diagnosed as having cancer at a late stage. For example, 72% of lung cancer patients, 57% of colorectal cancer patients, and 34% of breast cancer patients in the US are diagnosed at late stage. Traditionally, the diagnosis, screening and staging of cancer, as well as the evaluation of response to therapy have been primarily based on mammography, magnetic resonance imaging (MRI) and biopsy. These methods, although having a high detection rate, are expensive, time-consuming, invasive and uncomfortable, and have significant limitations for predicting a given tumor's potential for progression and response to treatment. There is, therefore, a need for an inexpensive, noninvasive, quick and simple tool with a high sensitivity and specificity for the detection of cancer biomarkers in aiding early cancer diagnosis, monitoring response to therapy and providing real-time prognostic information in patients with cancers. The proposed research for developing a hand-held cancer biomarker monitor is greatly needed for rapid, sensitive, low- cost, and multiplex detection of cancer biomarkers in human blood. Breast cancer biomarkers including carcinoenbryonic antigen (CEA), CA15-3 and human mammaglobin (HMAM) will be used as models to demonstrate the proof of principle. If the project is successful, the developed device can also be applied for the noninvasive monitoring of other tumor biomarkers in biological fluids such as blood.